X-ray calibration standard object

ABSTRACT

A standard reference plate is configured for insertion into an additive manufacturing apparatus for calibrating an electron beam of the additive manufacturing apparatus. The standard reference plate includes a lower plate and an upper plate being essentially in parallel and attached spaced apart from each other, the upper plate including a plurality of holes. A predetermined hollow pattern is provided inside the holes, and a spacing between the holes and the size of the holes and a distance between the upper plate and the lower plate and a position of an x-ray sensor of the additive manufacturing apparatus with respect to the standard reference plate are arranged so that x-rays emanating from the lower plate, when the electron beam is passing through a hollow part of the hollow pattern, will not pass directly from the lower plate through any one of the holes to the x-ray sensor.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of the U.S. patent application Ser.No. 15/245,542 filed Aug. 24, 2016, which claims the benefit of priorityunder 35 U.S.C. § 119(e) of U.S. Provisional Patent Application Ser. No.62/232,135, filed Sep. 24, 2015, the contents of both of which arehereby incorporated by reference in their entirety.

BACKGROUND Related Field

Various embodiments of the present invention relates to an X-raystandard reference object.

Description of Related Art

Freeform fabrication or additive manufacturing is a method for formingthree-dimensional articles through successive fusion of chosen parts ofpowder layers applied to a worktable. A method and apparatus accordingto this technique is disclosed in U.S. Pat. No. 8,187,521.

Such an apparatus may comprise a work table on which thethree-dimensional article is to be formed, a powder dispenser, arrangedto lay down a thin layer of powder on the work table for the formationof a powder bed, an energy beam source for delivering an energy beamspot to the powder whereby fusion of the powder takes place, elementsfor control of the energy beam spot over the powder bed for theformation of a cross section of the three-dimensional article throughfusion of parts of the powder bed, and a controlling computer, in whichinformation is stored concerning consecutive cross sections of thethree-dimensional article. A three-dimensional article is formed throughconsecutive fusions of consecutively formed cross sections of powderlayers, successively laid down by the powder dispenser.

In order to melt the powder material at specific locations there is aneed to inter alia verify the position and shape of the energy beamspot. One needs to know that the shape of the beam is within giventolerances at different positions on the work table. There is a need inthe art to easily verify that an electron beam spot has correct shapeand correct position.

BRIEF SUMMARY

Having this background, an object of the invention is to find means ofcalibration for an electron beam in an additive manufacturing apparatuswhich is accurate and easy to use.

The above-mentioned object is achieved by the features according to theclaims contained herein.

In a first aspect of various embodiments of the invention it is providedan X-ray standard reference object for calibrating a scanning electronbeam in an additive manufacturing apparatus by measuring X-ray signalsgenerated by scanning the electron beam onto the reference object, thereference object comprises: a lower and an upper plate being essentiallyin parallel and attached spaced apart from each other, the upper platecomprises a plurality of holes, wherein a predetermined hollow patternis provided inside the holes.

A non-limiting and exemplary advantage of this standard reference objectis that it is relatively simple and inexpensive to manufacture at thesame time as it provides for an accurate calibration of the electronbeam before starting to manufacture three-dimensional articles in theadditive manufacturing apparatus.

In various example embodiments the hollow pattern is a cross barpattern. A non-limiting and exemplary advantage of this embodiment isthat the relatively basic pattern provides for a quick and reliablecharacterization of the electron beam.

In various example embodiments the hollow pattern is equal for allholes. A non-limiting and exemplary advantage of this embodiment is thatthe pattern is easy to fabricate. In alternative various exampleembodiments the hollow pattern is different for different holes. Thecross bar pattern could for instance be arranged symmetric in the holefor holes arranged in the center of the standard reference object andmore and more asymmetric for holes further end further away from thecenter of the standard reference object.

In various example embodiments a spacing between the holes 20 and thesize of the holes 20 in the first plate 10, 25 and the distance betweenthe upper plate 19 and the lower plate 16 and the position of the x-raysensor 360 with respect to the standard reference object 100 arearranged so that x-ray emanating from the lower plate 16, 49 when atleast a portion of the electron beam is passing through a hollow part ofthe hollow pattern will not pass directly from the lower plate throughany one of the holes 20 to the detector 360. A non-limiting andexemplary advantage of this embodiment is high accuracy with little orno noise signal.

In various example embodiments the upper and lower plates are made ofthe same material. A non-limiting and exemplary advantage of thisembodiment is easy and cheap manufacturing.

In various example embodiments the upper plate comprises a first and asecond plate, the first plate comprises the holes, the second platecomprises the predetermined hollow pattern and wherein the second platefaces towards the lower plate. A non-limiting and exemplary advantage ofthis embodiment is that the accuracy of the positioning, size and shapecalibration may be improved since the thickness of the second platecomprising the predetermined hollow pattern may be relatively thin.

In various example embodiments the standard reference object comprisinga third plate arranged so that the second plate is arranged in betweenthe first and third plate. A non-limiting and exemplary advantage ofthis embodiment is that not only the first plate provides for coolingbut also a third plate, i.e., cooling from both sides of the secondplate which may be relatively warm during when scanning an electron beamover the predetermined pattern.

In various example embodiments the hollow pattern is made of a materialhaving a higher atomic number than the first, third and/or lower plate.A non-limiting and exemplary advantage of this embodiment is that higheratomic number material may produce more x-ray signal at the same time asthey can withstand heat better than low atomic number materials. Thismeans that a thinner second plate may be manufactured without risking adeformation during the use of the standard reference object. The secondplate may for instance be made of copper, molybdenum or tungsten or anyalloy thereof, whereas the first, third and/or lower plate is made ofaluminum.

In various example embodiments at least one hole in the first and/or thethird plate may have slanted walls. A non-limiting and exemplaryadvantage of this embodiment is that relatively large standard referenceobjects may be used without risking worse accuracy closer to itsperiphery.

In various example embodiments the holes may have different angles ofthe slanted walls depending on the position of the holes on the standardreference object 100.

The slanted walls may be arrange din both the first plate and the thirdplate. Holes further away from the center of the standard referenceobject may have a larger angle with respect to the normal to thestandard reference plate compared to holes closer to the center of theobject. A larger deflection of the electron beam may require a largerangle with respect to the normal of the standard reference object fornot hitting the first plate and/or the second plate instead of thepredetermined pattern, i.e., if not slanting the walls of the holes moreor less of the predetermined pattern will be hidden from the electronbeam depending on the degree of deflection.

In another non-limiting and exemplary embodiment the pattern is acontinuous pattern or a discontinuous pattern. A non-limiting andexemplary advantage of this embodiment is that any type of continuous ordiscontinuous pattern may be used for verifying the deflection speed.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Having thus described the invention in general terms, reference will nowbe made to the accompanying drawings, which are not necessarily drawn toscale, and wherein:

FIG. 1 depicts a schematic side view of a first example embodiment of astandard reference object;

FIG. 2 depicts a schematic view from above of the first exampleembodiment of the standard reference object;

FIG. 3 depicts an apparatus in which the inventive standard referenceobject may be implemented;

FIG. 4A depicts a schematic cross section along A-A in FIG. 2 of thestandard reference object; and

FIG. 4B depicts an alternative cross section of the standard referenceobject.

FIG. 5 is a block diagram of an exemplary system according to variousembodiments of the present invention

FIG. 6A is a schematic block diagram of a server according to variousembodiments of the present invention.

FIG. 6B is a schematic block diagram of an exemplary mobile deviceaccording to various embodiments of the present invention.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

Various embodiments of the present invention will now be described morefully hereinafter with reference to the accompanying drawings, in whichsome, but not all embodiments of the invention are shown. Indeed,embodiments of the invention may be embodied in many different forms andshould not be construed as limited to the embodiments set forth herein.Rather, these embodiments are provided so that this disclosure willsatisfy applicable legal requirements. Unless otherwise defined, alltechnical and scientific terms used herein have the same meaning ascommonly known and understood by one of ordinary skill in the art towhich the invention relates. The term “or” is used herein in both thealternative and conjunctive sense, unless otherwise indicated. Likenumbers refer to like elements throughout.

Still further, to facilitate the understanding of this invention, anumber of terms are defined below. Terms defined herein have meanings ascommonly understood by a person of ordinary skill in the areas relevantto the present invention. Terms such as “a”, “an” and “the” are notintended to refer to only a singular entity, but include the generalclass of which a specific example may be used for illustration. Theterminology herein is used to describe specific embodiments of theinvention, but their usage does not delimit the invention, except asoutlined in the claims.

The term “three-dimensional structures” and the like as used hereinrefer generally to intended or actually fabricated three-dimensionalconfigurations (e.g., of structural material or materials) that areintended to be used for a particular purpose. Such structures, etc. may,for example, be designed with the aid of a three-dimensional CAD system.

The term “electron beam” as used herein in various embodiments refers toany charged particle beam. The sources of charged particle beam caninclude an electron gun, a linear accelerator and so on.

FIG. 3 depicts an example embodiment of a freeform fabrication oradditive manufacturing apparatus 300 in which the inventive X-raystandard reference object may be implemented. The apparatus 300 in atleast this embodiment comprises an electron gun 302; two powder hoppers306, 307; a start plate 316; a build tank 312; a powder distributor 310;a build platform 314; an X-ray sensor 360; and a vacuum chamber 320.

The vacuum chamber 320 is capable of maintaining a vacuum environment bymeans of or via a vacuum system, which system may comprise aturbomolecular pump, a scroll pump, an ion pump and one or more valveswhich are well known to a skilled person in the art and therefore needno further explanation in this context. The vacuum system may becontrolled by a control unit 350.

The electron gun 302 is generating an electron beam 380 which may beused for melting or fusing together powder material 318 provided on thestart plate 316. The electron gun 302 may be provided in the vacuumchamber 320. The control unit 350 may be used for controlling andmanaging the electron beam 380 emitted from the electron beam gun 302.At least one focusing coil (not shown), at least one deflection coil(not shown) and an electron beam power supply (not shown) may beelectrically connected to the control unit 350. In an example embodimentof the invention the electron gun generates a focusable electron beamwith an accelerating voltage of about 60 kV and with a beam power in therange of 0-10 kW. The pressure in the vacuum chamber may be in the rangeof 1×10⁻³-1×10⁻⁶ mBar when building the three-dimensional article byfusing the powder layer by layer with the energy beam.

The powder hoppers 306, 307 comprise the powder material to be providedon the start plate 316 in the build tank 312. The powder material mayfor instance be pure metals or metal alloys such as titanium, titaniumalloys, aluminum, aluminum alloys, stainless steel, Co—Cr—W alloy, etc.

The powder distributor 310 is arranged to lay down a thin layer of thepowder material on the start plate 316. During a work cycle the buildplatform 314 will be lowered successively in relation to the ray gunafter each added layer of powder material. In order to make thismovement possible, the build platform 314 is in one embodiment of theinvention arranged movably in vertical direction, i.e., in the directionindicated by arrow P. This means that the build platform 314 starts inan initial position, in which a first powder material layer of necessarythickness has been laid down on the start plate 316. The build platformis thereafter lowered in connection with laying down a new powdermaterial layer for the formation of a new cross section of athree-dimensional article. Means for lowering the build platform 314 mayfor instance be through a servo engine equipped with a gear, adjustingscrews etc.

A model of the three dimensional article may be generated via a CAD(Computer Aided Design) tool.

After a first layer is finished, i.e., the fusion of powder material formaking a first layer of the three-dimensional article, a second powderlayer is provided on the work table 316. The second powder layer isdistributed according to the same manner as the previous layer. However,there might be alternative methods in the same additive manufacturingmachine for distributing powder onto the work table. For instance, afirst layer may be provided by means of or via a first powderdistributor, a second layer may be provided by another powderdistributor. The design of the powder distributor is automaticallychanged according to instructions from the control unit. A powderdistributor in the form of a single rake system, i.e., where one rake iscatching powder fallen down from both a left powder hopper 306 and aright powder hopper 307, the rake as such can change design.

After having distributed the second powder layer on the work table 316,the electron beam 380 is directed over the build platform causing thesecond powder layer to fuse in selected locations to form a second crosssection of the three-dimensional article. Fused portions in the secondlayer may be bonded to fused portions of the first layer. The fusedportions in the first and second layer may be melted together by meltingnot only the powder in the uppermost layer but also remelting at least afraction of a thickness of a layer directly below the uppermost layer.

FIG. 1 depicts a schematic side view of a first example embodiment of anX-ray standard reference object 100 according to the present invention.In this example embodiment the X-ray standard reference object 100comprises a lower plate 16 and an upper plate 19 being attached spacedapart from each other so that the upper and lower plate 19 and 16respectively are essentially parallel to each other. In FIG. 1 the upperand lower plates are attached to each other via a plurality of distances18 which may be fastened to the upper and lower plates via screws orrivets or similar fastening elements. The lower plate 16 is essentiallyflat. The upper plate 19 comprises a predetermined number of holes 20,see FIG. 2. Inside the holes 20 it is arranged a predetermined hollowpattern 22.

In a first example embodiment the holes 20 and the pattern 22 ismanufactured out of one and the same upper plate 19. The holes 20 withthe pattern 22 may be manufactured through etching.

In a second example embodiment the upper plate comprises a first 10 anda second 12 plate, wherein the first plate 10 comprises thepredetermined number of holes 20 and where the second plate 12 comprisesthe pattern 22. The holes 20 may be water cut or drilled. The secondplate 12 may be a net having the predetermined pattern or a solid platehaving the predetermined pattern only at selected locations aligned withthe first plate's holes 20. The predetermined pattern is the secondplate 12 may be made through etching. The second plate 12 is facingtowards the lower plate 16. The second plate 12 may be thinner comparedto the first plate 10. In various example embodiments the thickness ofthe second plate is 0.05-0.20 mm. In various example embodiments thethickness of the first and/or third plate may be a 1-3 cm. In variousexample embodiments the diameter of the holes 20 is 0.5-2 cm.

The bars in the predetermined pattern 22 may have sharp edges forimproving the accuracy of the knife edge beam profiling method which maybe used for determining the position, size and shape of the electronbeam.

In various example embodiments a distance between the upper and lowerplate may be 5-10 cm.

The second plate may be made of different material compared to the firstplate. The second plate 12 may be made of a material having a largeratomic number than the first plate 10. The second plate may be made ofCu, or W whereas the first plate 10 may be made of μl. The pattern 22may be a net with bars crossing each other at a predetermined angle. Alateral thickness of the bars may in an example embodiment be ⅓ of thediameter of the hole 20. In another example embodiment the lateralthickness of the bars may be ⅕ of the diameter or smaller.

In a third embodiment the upper plate 19 comprises a first, second and athird plate 10, 12, 14 respectively. The second plate 12, 46 is arrangedin between the first 10 and third plate 14. The third plate may beessentially thicker than the first 48 and second plate 46, see FIG. 4A.In an example embodiment the third plate 44 is 5 times as thick as thefirst plate 48. The third plate 44, 14 comprises holes 45 aligned withthe holes 40 in the first plate 10, 48. The holes 45 in the third plate44 may have a conical shape denoted by 41 in FIG. 4A, i.e., having alarger diameter facing towards the lower plate 16, 49 than towards thesecond plate 12, 46. The conical shape is used for improving thesignal/noise ratio for the x-ray signal. If using a straight cylinder,x-ray may emanate from its walls. By slanting the inner walls of theholes the x-ray signal may be heavily suppressed. The thickness of thethird plate 44 and the distance between the third plate 44 and the lowerplate 49, 16 may be adjusted in order to improve the signal/noise ratioas much as possible so that X-ray signals detected above the first plate48 will emanate from the predetermined pattern 42 or the first plate 48,10 only.

In the second and third embodiment the second plate may be made of arelatively heavy material compared to its surrounding, i.e., the firstplate 10, 48 and third plate 14, 44.

A spacing between the holes 20 in the first plate 10, 25 and thedistance between the upper plate 19 and the lower plate 16 and theposition of the x-ray sensor 360 with respect to the standard referenceobject 100 are determined so that x-ray emanating from the lower plate16, 49 will be out of sight for the detector 360, i.e., x-ray will notpass directly from the lower plate through the hole 20 to the detector360.

The pattern 22 may be a cross pattern. The cross pattern may have itscenter in the center of the hole 20. Alternatively the center of thecross is not aligned with the center of the hole 20.

In various example embodiments different holes 20 may have differentpatterns. For instance a first hole may have a first cross pattern and asecond hole 20 may have a second cross pattern. The difference betweenthe cross pattern may be the angles between the cross bars.

FIG. 4B depicts an alternative cross section of the standard referenceobject. In this embodiment the first plate 48 is thicker than in theembodiment as shown in FIG. 4A. Because the first plate 48 is thickerthe holes 40 in the first plate needs to have slanted walls 43. Thereason for using the slanted walls is that the electron beam should beable to impinge on all areas of the predetermined pattern 42. Withoutslanted walls some regions of the pattern 22 will be out of sigh fromthe electron beam.

The first and third plate may be identical.

An angle of the slanted walls 41, 43 may be larger with respect to anormal to a surface of the standard reference object the further awaythe holes are from a center of the standard reference object. This meansthat in various example embodiments the holes may have different anglesof the slanted walls depending on the position of the holes on thestandard reference object 100.

The electron beam source 302 is used for generating an electron beam 380which may be deflected on the work table 314 of or via at least onedeflection coil (not shown) controlled by the control unit 350. Bychanging the magnetic field of the deflection coil the electron beam 380may be moved at any desired position within a predetermined maximumarea. A focus coil (not shown) may be used for changing the spot size ofthe electron beam on a target area. An astigmatism lens (not shown) maybe used for changing the spot shape of the electron beam on the targetarea.

The X-ray standard reference object 100 may be used to calibrate anelectron beam in an additive manufacturing apparatus. The x-ray standardreference object may be arranged on the build platform 314 beforestarting to manufacture any parts in the machine. An electron beam isswept over the x-ray standard reference object and an X-ray detector isused for collecting x-ray signals generated from the object 100 as theelectron beam sweeps over it. The holes 20 are arranged at well-definedpositions on the object 100. By analyzing the X-ray signal as theelectron beam is sweeping over the object one may determine the shape,speed and absolute position of the electron beam. The spot size of theelectron beam is typically smaller than the hollow portions of thepredetermined pattern. As the electron beam is swept over a given holeone can determine the edge of the hole and the edge of the predeterminedpattern as distinct signals. As the dimension of the holes and thepredetermined pattern is known beforehand with high accuracy, one canfrom a given sweeping pattern determine the shape, position and scanningspeed of the electron beam. Calibration parameters may be stored in alook-up table for use when manufacturing three-dimensional objects.

The beam characterization method that may be used is the “knife edgebeam profiling method”. When an electron beam hits the edge material(edge of the predetermined pattern), x-ray photons are generated anddetected by the detector 361. The signal from the X-ray detector 361 asthe beam is swept over the edge of the predetermined pattern may berecorded by an oscilloscope. The shape of the detected signal may thenbe translated to a beam diameter, beam shape and beam position. Aposition of the individual holes may be determined from a SEM image. Thebeam may then be swept over a predetermined hole 20 from left to right.When a first line is exposed a new scan starts with a predeterminedshift in a vertical direction. The predetermined shift may be 0.2 mm.The procedure is repeated until the full predetermined pattern 22 iscovered. The signal from the X-ray detector is recorded continuously bythe oscilloscope from the first to the last scan line.

The beam size and position calibration exposure procedure is dependenton heat distribution and dissipation. Since exposing one singlecalibration site at a time would generate too much heat in thepredetermined pattern 22 so that the material most probably willdeteriorate. However, if several calibration sites (holes) are exposedin one single loop the heat generated in the predetermined pattern 22will have to dissipate. From the detected oscilloscope signal it ispossible, if enough samples are acquired, to determine the size, shapeand position of the electron beam. The scan signal is basically thederivative of the corresponding Gaussian beam profile. The knife edgemethod optimizes an error function to the scan data by fitting theerf(r, a), where r is the 1/e² radius and “a” is the flank position.

If the detected electron beam at a given position on the X-ray standardreference object is determined to be misshaped, adjustment by theastigmatism lens may correct for the beam shape distortions. X-raydetection may continue for the position during adjustment until adesired shape is achieved. By sweeping the electron beam across thepattern in different directions one may determine the shape of theelectron beam spot with high accuracy for each and every position on theX-ray standard reference object.

If the detected electron beam at a given position on the X-ray standardreference object 100 is determined to be out of size, adjustment by thefocus lens may correct for the beam size distortion. X-ray detection maycontinue for the position during adjustment until a desired size isachieved. By sweeping the electron beam across the pattern in differentdirections one may determine the size of the electron beam spot withhigh accuracy for each and every position on the X-ray standardreference object.

The use of the X-ray standard reference object may be before each newmanufacture of the machine or after a predetermined number ofmanufactures. The X-ray standard reference object may be used as soon asa critical components has been renewed or exchanged in the additivemanufacturing machine, such as exchange of electron filament.

In another aspect of the invention it is provided a program elementconfigured and arranged, when executed on a computer, to implement amethod for forming at least one three-dimensional article throughsuccessive joining of parts of a material layer. The program element mayspecifically be configured to perform the steps as outlined in the claimset provided herein.

The program element may be installed in one or more non-transitorycomputer readable storage mediums. The non-transitory computer readablestorage mediums and/or the program element may be associated with acontrol unit, as described elsewhere herein. The computer readablestorage mediums and the program elements, which may comprisenon-transitory computer-readable program code portions embodied therein,may further be contained within one or more non-transitory computerprogram products. According to various embodiments, the method describedelsewhere herein may be computer-implemented, for example in conjunctionwith one or more processors and/or memory storage areas.

As mentioned, various embodiments of the present invention may beimplemented in various ways, including as non-transitory computerprogram products. A computer program product may include anon-transitory computer-readable storage medium storing applications,programs, program modules, scripts, source code, program code, objectcode, byte code, compiled code, interpreted code, machine code,executable instructions, and/or the like (also referred to herein asexecutable instructions, instructions for execution, program code,and/or similar terms used herein interchangeably). Such non-transitorycomputer-readable storage media include all computer-readable media(including volatile and non-volatile media).

In one embodiment, a non-volatile computer-readable storage medium mayinclude a floppy disk, flexible disk, hard disk, solid-state storage(SSS) (e.g., a solid state drive (SSD), solid state card (SSC), solidstate module (SSM)), enterprise flash drive, magnetic tape, or any othernon-transitory magnetic medium, and/or the like. A non-volatilecomputer-readable storage medium may also include a punch card, papertape, optical mark sheet (or any other physical medium with patterns ofholes or other optically recognizable indicia), compact disc read onlymemory (CD-ROM), compact disc compact disc-rewritable (CD-RW), digitalversatile disc (DVD), Blu-ray disc (BD), any other non-transitoryoptical medium, and/or the like. Such a non-volatile computer-readablestorage medium may also include read-only memory (ROM), programmableread-only memory (PROM), erasable programmable read-only memory (EPROM),electrically erasable programmable read-only memory (EEPROM), flashmemory (e.g., Serial, NAND, NOR, and/or the like), multimedia memorycards (MMC), secure digital (SD) memory cards, SmartMedia cards,CompactFlash (CF) cards, Memory Sticks, and/or the like. Further, anon-volatile computer-readable storage medium may also includeconductive-bridging random access memory (CBRAM), phase-change randomaccess memory (PRAM), ferroelectric random-access memory (FeRAM),non-volatile random-access memory (NVRAM), magnetoresistiverandom-access memory (MRAM), resistive random-access memory (RRAM),Silicon-Oxide-Nitride-Oxide-Silicon memory (SONOS), floating junctiongate random access memory (FJG RAM), Millipede memory, racetrack memory,and/or the like.

In one embodiment, a volatile computer-readable storage medium mayinclude random access memory (RAM), dynamic random access memory (DRAM),static random access memory (SRAM), fast page mode dynamic random accessmemory (FPM DRAM), extended data-out dynamic random access memory (EDODRAM), synchronous dynamic random access memory (SDRAM), double datarate synchronous dynamic random access memory (DDR SDRAM), double datarate type two synchronous dynamic random access memory (DDR2 SDRAM),double data rate type three synchronous dynamic random access memory(DDR3 SDRAM), Rambus dynamic random access memory (RDRAM), TwinTransistor RAM (TTRAM), Thyristor RAM (T-RAM), Zero-capacitor (Z-RAM),Rambus in-line memory module (RIMM), dual in-line memory module (DIMM),single in-line memory module (SIMM), video random access memory VRAM,cache memory (including various levels), flash memory, register memory,and/or the like. It will be appreciated that where embodiments aredescribed to use a computer-readable storage medium, other types ofcomputer-readable storage media may be substituted for or used inaddition to the computer-readable storage media described above.

As should be appreciated, various embodiments of the present inventionmay also be implemented as methods, apparatus, systems, computingdevices, computing entities, and/or the like, as have been describedelsewhere herein. As such, embodiments of the present invention may takethe form of an apparatus, system, computing device, computing entity,and/or the like executing instructions stored on a computer-readablestorage medium to perform certain steps or operations. However,embodiments of the present invention may also take the form of anentirely hardware embodiment performing certain steps or operations.

Various embodiments are described below with reference to block diagramsand flowchart illustrations of apparatuses, methods, systems, andcomputer program products. It should be understood that each block ofany of the block diagrams and flowchart illustrations, respectively, maybe implemented in part by computer program instructions, e.g., aslogical steps or operations executing on a processor in a computingsystem. These computer program instructions may be loaded onto acomputer, such as a special purpose computer or other programmable dataprocessing apparatus to produce a specifically-configured machine, suchthat the instructions which execute on the computer or otherprogrammable data processing apparatus implement the functions specifiedin the flowchart block or blocks.

These computer program instructions may also be stored in acomputer-readable memory that can direct a computer or otherprogrammable data processing apparatus to function in a particularmanner, such that the instructions stored in the computer-readablememory produce an article of manufacture including computer-readableinstructions for implementing the functionality specified in theflowchart block or blocks. The computer program instructions may also beloaded onto a computer or other programmable data processing apparatusto cause a series of operational steps to be performed on the computeror other programmable apparatus to produce a computer-implementedprocess such that the instructions that execute on the computer or otherprogrammable apparatus provide operations for implementing the functionsspecified in the flowchart block or blocks.

Accordingly, blocks of the block diagrams and flowchart illustrationssupport various combinations for performing the specified functions,combinations of operations for performing the specified functions andprogram instructions for performing the specified functions. It shouldalso be understood that each block of the block diagrams and flowchartillustrations, and combinations of blocks in the block diagrams andflowchart illustrations, could be implemented by special purposehardware-based computer systems that perform the specified functions oroperations, or combinations of special purpose hardware and computerinstructions.

FIG. 5 is a block diagram of an exemplary system 1020 that can be usedin conjunction with various embodiments of the present invention. In atleast the illustrated embodiment, the system 1020 may include one ormore central computing devices 1110, one or more distributed computingdevices 1120, and one or more distributed handheld or mobile devices1300, all configured in communication with a central server 1200 (orcontrol unit) via one or more networks 1130. While FIG. 5 illustratesthe various system entities as separate, standalone entities, thevarious embodiments are not limited to this particular architecture.

According to various embodiments of the present invention, the one ormore networks 1130 may be capable of supporting communication inaccordance with any one or more of a number of second-generation (2G),2.5G, third-generation (3G), and/or fourth-generation (4G) mobilecommunication protocols, or the like. More particularly, the one or morenetworks 1130 may be capable of supporting communication in accordancewith 2G wireless communication protocols IS-136 (TDMA), GSM, and IS-95(CDMA). Also, for example, the one or more networks 1130 may be capableof supporting communication in accordance with 2.5G wirelesscommunication protocols GPRS, Enhanced Data GSM Environment (EDGE), orthe like. In addition, for example, the one or more networks 1130 may becapable of supporting communication in accordance with 3G wirelesscommunication protocols such as Universal Mobile Telephone System (UMTS)network employing Wideband Code Division Multiple Access (WCDMA) radioaccess technology. Some narrow-band AMPS (NAMPS), as well as TACS,network(s) may also benefit from embodiments of the present invention,as should dual or higher mode mobile stations (e.g., digital/analog orTDMA/CDMA/analog phones). As yet another example, each of the componentsof the system 1020 may be configured to communicate with one another inaccordance with techniques such as, for example, radio frequency (RF),Bluetooth™ infrared (IrDA), or any of a number of different wired orwireless networking techniques, including a wired or wireless PersonalArea Network (“PAN”), Local Area Network (“LAN”), Metropolitan AreaNetwork (“MAN”), Wide Area Network (“WAN”), or the like.

Although the device(s) 1110-1300 are illustrated in FIG. 5 ascommunicating with one another over the same network 1130, these devicesmay likewise communicate over multiple, separate networks.

According to one embodiment, in addition to receiving data from theserver 1200, the distributed devices 1110, 1120, and/or 1300 may befurther configured to collect and transmit data on their own. In variousembodiments, the devices 1110, 1120, and/or 1300 may be capable ofreceiving data via one or more input units or devices, such as a keypad,touchpad, barcode scanner, radio frequency identification (RFID) reader,interface card (e.g., modem, etc.) or receiver. The devices 1110, 1120,and/or 1300 may further be capable of storing data to one or morevolatile or non-volatile memory modules, and outputting the data via oneor more output units or devices, for example, by displaying data to theuser operating the device, or by transmitting data, for example over theone or more networks 1130.

In various embodiments, the server 1200 includes various systems forperforming one or more functions in accordance with various embodimentsof the present invention, including those more particularly shown anddescribed herein. It should be understood, however, that the server 1200might include a variety of alternative devices for performing one ormore like functions, without departing from the spirit and scope of thepresent invention. For example, at least a portion of the server 1200,in certain embodiments, may be located on the distributed device(s)1110, 1120, and/or the handheld or mobile device(s) 1300, as may bedesirable for particular applications. As will be described in furtherdetail below, in at least one embodiment, the handheld or mobiledevice(s) 1300 may contain one or more mobile applications 1330 whichmay be configured so as to provide a user interface for communicationwith the server 1200, all as will be likewise described in furtherdetail below.

FIG. 6A is a schematic diagram of the server 1200 according to variousembodiments. The server 1200 includes a processor 1230 that communicateswith other elements within the server via a system interface or bus1235. Also included in the server 1200 is a display/input device 1250for receiving and displaying data. This display/input device 1250 maybe, for example, a keyboard or pointing device that is used incombination with a monitor. The server 1200 further includes memory1220, which typically includes both read only memory (ROM) 1226 andrandom access memory (RAM) 1222. The server's ROM 1226 is used to storea basic input/output system 1224 (BIOS), containing the basic routinesthat help to transfer information between elements within the server1200. Various ROM and RAM configurations have been previously describedherein.

In addition, the server 1200 includes at least one storage device orprogram storage 210, such as a hard disk drive, a floppy disk drive, aCD Rom drive, or optical disk drive, for storing information on variouscomputer-readable media, such as a hard disk, a removable magnetic disk,or a CD-ROM disk. As will be appreciated by one of ordinary skill in theart, each of these storage devices 1210 are connected to the system bus1235 by an appropriate interface. The storage devices 1210 and theirassociated computer-readable media provide nonvolatile storage for apersonal computer. As will be appreciated by one of ordinary skill inthe art, the computer-readable media described above could be replacedby any other type of computer-readable media known in the art. Suchmedia include, for example, magnetic cassettes, flash memory cards,digital video disks, and Bernoulli cartridges.

Although not shown, according to an embodiment, the storage device 1210and/or memory of the server 1200 may further provide the functions of adata storage device, which may store historical and/or current deliverydata and delivery conditions that may be accessed by the server 1200. Inthis regard, the storage device 1210 may comprise one or more databases.The term “database” refers to a structured collection of records or datathat is stored in a computer system, such as via a relational database,hierarchical database, or network database and as such, should not beconstrued in a limiting fashion.

A number of program modules (e.g., exemplary modules 1400-1700)comprising, for example, one or more computer-readable program codeportions executable by the processor 1230, may be stored by the variousstorage devices 1210 and within RAM 1222. Such program modules may alsoinclude an operating system 1280. In these and other embodiments, thevarious modules 1400, 1500, 1600, 1700 control certain aspects of theoperation of the server 1200 with the assistance of the processor 1230and operating system 1280. In still other embodiments, it should beunderstood that one or more additional and/or alternative modules mayalso be provided, without departing from the scope and nature of thepresent invention.

In various embodiments, the program modules 1400, 1500, 1600, 1700 areexecuted by the server 1200 and are configured to generate one or moregraphical user interfaces, reports, instructions, and/ornotifications/alerts, all accessible and/or transmittable to varioususers of the system 1020. In certain embodiments, the user interfaces,reports, instructions, and/or notifications/alerts may be accessible viaone or more networks 1130, which may include the Internet or otherfeasible communications network, as previously discussed.

In various embodiments, it should also be understood that one or more ofthe modules 1400, 1500, 1600, 1700 may be alternatively and/oradditionally (e.g., in duplicate) stored locally on one or more of thedevices 1110, 1120, and/or 1300 and may be executed by one or moreprocessors of the same. According to various embodiments, the modules1400, 1500, 1600, 1700 may send data to, receive data from, and utilizedata contained in one or more databases, which may be comprised of oneor more separate, linked and/or networked databases.

Also located within the server 1200 is a network interface 1260 forinterfacing and communicating with other elements of the one or morenetworks 1130. It will be appreciated by one of ordinary skill in theart that one or more of the server 1200 components may be locatedgeographically remotely from other server components. Furthermore, oneor more of the server 1200 components may be combined, and/or additionalcomponents performing functions described herein may also be included inthe server.

While the foregoing describes a single processor 1230, as one ofordinary skill in the art will recognize, the server 1200 may comprisemultiple processors operating in conjunction with one another to performthe functionality described herein. In addition to the memory 1220, theprocessor 1230 can also be connected to at least one interface or othermeans for displaying, transmitting and/or receiving data, content or thelike. In this regard, the interface(s) can include at least onecommunication interface or other means for transmitting and/or receivingdata, content or the like, as well as at least one user interface thatcan include a display and/or a user input interface, as will bedescribed in further detail below. The user input interface, in turn,can comprise any of a number of devices allowing the entity to receivedata from a user, such as a keypad, a touch display, a joystick or otherinput device.

Still further, while reference is made to the “server” 1200, as one ofordinary skill in the art will recognize, embodiments of the presentinvention are not limited to traditionally defined server architectures.Still further, the system of embodiments of the present invention is notlimited to a single server, or similar network entity or mainframecomputer system. Other similar architectures including one or morenetwork entities operating in conjunction with one another to providethe functionality described herein may likewise be used withoutdeparting from the spirit and scope of embodiments of the presentinvention. For example, a mesh network of two or more personal computers(PCs), similar electronic devices, or handheld portable devices,collaborating with one another to provide the functionality describedherein in association with the server 1200 may likewise be used withoutdeparting from the spirit and scope of embodiments of the presentinvention.

According to various embodiments, many individual steps of a process mayor may not be carried out utilizing the computer systems and/or serversdescribed herein, and the degree of computer implementation may vary, asmay be desirable and/or beneficial for one or more particularapplications.

FIG. 6B provides an illustrative schematic representative of a mobiledevice 1300 that can be used in conjunction with various embodiments ofthe present invention. Mobile devices 1300 can be operated by variousparties. As shown in FIG. 6B, a mobile device 1300 may include anantenna 1312, a transmitter 1304 (e.g., radio), a receiver 1306 (e.g.,radio), and a processing element 1308 that provides signals to andreceives signals from the transmitter 1304 and receiver 1306,respectively.

The signals provided to and received from the transmitter 1304 and thereceiver 1306, respectively, may include signaling data in accordancewith an air interface standard of applicable wireless systems tocommunicate with various entities, such as the server 1200, thedistributed devices 1110, 1120, and/or the like. In this regard, themobile device 1300 may be capable of operating with one or more airinterface standards, communication protocols, modulation types, andaccess types. More particularly, the mobile device 1300 may operate inaccordance with any of a number of wireless communication standards andprotocols. In a particular embodiment, the mobile device 1300 mayoperate in accordance with multiple wireless communication standards andprotocols, such as GPRS, UMTS, CDMA2000, 1×RTT, WCDMA, TD-SCDMA, LTE,E-UTRAN, EVDO, HSPA, HSDPA, Wi-Fi, WiMAX, UWB, IR protocols, Bluetoothprotocols, USB protocols, and/or any other wireless protocol.

Via these communication standards and protocols, the mobile device 1300may according to various embodiments communicate with various otherentities using concepts such as Unstructured Supplementary Service data(USSD), Short Message Service (SMS), Multimedia Messaging Service (MMS),Dual-Tone Multi-Frequency Signaling (DTMF), and/or Subscriber IdentityModule Dialer (SIM dialer). The mobile device 1300 can also downloadchanges, add-ons, and updates, for instance, to its firmware, software(e.g., including executable instructions, applications, programmodules), and operating system.

According to one embodiment, the mobile device 1300 may include alocation determining device and/or functionality. For example, themobile device 1300 may include a GPS module adapted to acquire, forexample, latitude, longitude, altitude, geocode, course, and/or speeddata. In one embodiment, the GPS module acquires data, sometimes knownas ephemeris data, by identifying the number of satellites in view andthe relative positions of those satellites.

The mobile device 1300 may also comprise a user interface (that caninclude a display 1316 coupled to a processing element 1308) and/or auser input interface (coupled to a processing element 308). The userinput interface can comprise any of a number of devices allowing themobile device 1300 to receive data, such as a keypad 1318 (hard orsoft), a touch display, voice or motion interfaces, or other inputdevice. In embodiments including a keypad 1318, the keypad can include(or cause display of) the conventional numeric (0-9) and related keys(#, *), and other keys used for operating the mobile device 1300 and mayinclude a full set of alphabetic keys or set of keys that may beactivated to provide a full set of alphanumeric keys. In addition toproviding input, the user input interface can be used, for example, toactivate or deactivate certain functions, such as screen savers and/orsleep modes.

The mobile device 1300 can also include volatile storage or memory 1322and/or non-volatile storage or memory 1324, which can be embedded and/ormay be removable. For example, the non-volatile memory may be ROM, PROM,EPROM, EEPROM, flash memory, MMCs, SD memory cards, Memory Sticks,CBRAM, PRAM, FeRAM, RRAM, SONOS, racetrack memory, and/or the like. Thevolatile memory may be RAM, DRAM, SRAM, FPM DRAM, EDO DRAM, SDRAM, DDRSDRAM, DDR2 SDRAM, DDR3 SDRAM, RDRAM, RIMM, DIMM, SIMM, VRAM, cachememory, register memory, and/or the like. The volatile and non-volatilestorage or memory can store databases, database instances, databasemapping systems, data, applications, programs, program modules, scripts,source code, object code, byte code, compiled code, interpreted code,machine code, executable instructions, and/or the like to implement thefunctions of the mobile device 1300.

The mobile device 1300 may also include one or more of a camera 1326 anda mobile application 1330. The camera 1326 may be configured accordingto various embodiments as an additional and/or alternative datacollection feature, whereby one or more items may be read, stored,and/or transmitted by the mobile device 1300 via the camera. The mobileapplication 1330 may further provide a feature via which various tasksmay be performed with the mobile device 1300. Various configurations maybe provided, as may be desirable for one or more users of the mobiledevice 1300 and the system 1020 as a whole.

It will be appreciated that many variations of the above systems andmethods are possible, and that deviation from the above embodiments arepossible, but yet within the scope of the claims. Many modifications andother embodiments of the invention set forth herein will come to mind toone skilled in the art to which these inventions pertain having thebenefit of the teachings presented in the foregoing descriptions and theassociated drawings. Such modifications may, for example, involve usingdifferent materials in the X-ray standard reference object. Therefore,it is to be understood that the inventions are not to be limited to thespecific embodiments disclosed and that modifications and otherembodiments are intended to be included within the scope of the appendedclaims. Although specific terms are employed herein, they are used in ageneric and descriptive sense only and not for purposes of limitation.

1. A standard reference plate configured for insertion into an electronbeam additive manufacturing apparatus for calibrating a size, shape, andposition of an electron beam of the electron beam additive manufacturingapparatus, wherein the standard reference plate is configured forremoval from the additive manufacturing apparatus after the calibrating,the standard reference plate comprising: a lower plate and an upperplate being essentially in parallel and attached spaced apart from eachother, the upper plate comprising a plurality of holes, wherein apredetermined hollow pattern is provided inside the holes, wherein aspacing between the holes and the size of the holes and a distancebetween the upper plate and the lower plate and a position of an x-raysensor of the additive manufacturing apparatus with respect to thestandard reference plate are arranged so that x-rays emanating from thelower plate, when at least a portion of the electron beam is passingthrough a hollow part of the hollow pattern, will not pass directly fromthe lower plate through any one of the holes to the x-ray sensor.
 2. Thestandard reference plate of claim 1, wherein: the upper plate comprisesa first and a second plate; the first plate comprises the plurality ofholes; and the second plate comprises the predetermined hollow pattern.3. The standard reference plate of claim 2, wherein the second plate ishas a thickness that is at most one fifth of a thickness of the firstplate.
 4. The standard reference plate of claim 2, wherein: the upperplate further comprises a third plate comprising an additional pluralityof holes aligned with the plurality of holes of the first plate; and thesecond plate is positioned between the first plate and the third plate.5. The standard reference plate of claim 4, wherein the third plate isthicker than both the first plate and the second plate.
 6. The standardreference plate of claim 4, wherein the plurality of additional holes inthe third plate have a conical shape such that diameter of each of theplurality of additional holes increases with decreasing distance fromthe lower plate.
 7. The standard reference plate of claim 4, whereinsecond plate is constructed from a heavier material than the first andthird plates.
 8. The standard reference plate according to claim 1,wherein the hollow pattern is a cross bar pattern.
 9. The standardreference plate according to claim 1, wherein the hollow pattern isidentical for all holes.
 10. The standard reference plate according toclaim 1, wherein the upper and lower plates are made of the samematerial.
 11. A standard reference plate configured for insertion intoan electron beam additive manufacturing apparatus for calibrating asize, shape, and position of an electron beam of the electron beamadditive manufacturing apparatus, wherein the standard reference plateis configured for removal from the additive manufacturing apparatusafter the calibrating, the standard reference plate comprising: an upperplate comprising a first plate and a second plate, wherein the firstplate comprises a plurality of holes and the second plate comprises apredetermined hollow pattern aligned with the plurality of holes; and alower plate spaced apart from the upper plate, wherein a spacing betweenthe holes and a size of the holes and a distance between the upper plateand the lower plate and a position of an x-ray sensor of the additivemanufacturing apparatus with respect to the standard reference plate arearranged so that x-rays emanating from the lower plate, when at least aportion of the electron beam is passing through a hollow part of thehollow pattern, will not pass directly from the lower plate through anyone of the plurality of holes to the x-ray sensor.
 12. The standardreference plate of claim 11, wherein: the upper plate further comprisesa third plate comprising an additional plurality of holes aligned withthe plurality of holes of the first plate; and the second plate ispositioned between the first plate and the third plate.
 13. The standardreference plate of claim 12, wherein the third plate is thicker thanboth the first plate and the second plate.
 14. The standard referenceplate of claim 12, wherein the plurality of additional holes in thethird plate have a conical shape such that diameter of each of theplurality of additional holes increases with decreasing distance fromthe lower plate.
 15. The standard reference plate of claim 12, whereinsecond plate is constructed from a heavier material than the first andthird plates.
 16. The standard reference plate of claim 11, wherein thehollow pattern is made of a material having a higher atomic number thanthe first plate.
 17. The standard reference plate according to claim 11,wherein the hollow pattern is a cross bar pattern.
 18. The standardreference plate according to claim 11, wherein the hollow pattern isidentical for all holes.
 19. The standard reference plate according toclaim 11, wherein the upper and lower plates are made of the samematerial.
 20. Use of a standard reference plate in an additivemanufacturing apparatus having an electron beam for melting powder layerby layer according to a predetermined pattern, wherein the standardreference plate is inserted for calibrating a size, shape and positionof an electron beam and then removed before starting to manufacturethree-dimensional articles with the additive manufacturing apparatus,wherein the standard reference plate comprises: a lower and an upperplate being essentially in parallel and attached spaced apart from eachother, the upper plate comprising a plurality of holes, wherein apredetermined hollow pattern is provided-inside the holes, wherein theupper plate comprises a first and a second plate, the first platecomprising the holes, the second plate comprising the predeterminedhollow pattern and wherein the second plate is positioned between thefirst plate and the lower plate, wherein a spacing between the holes anda size of the holes in the first plate and a distance between the upperplate and the lower plate and a position of an x-ray sensor with respectto the standard reference plate are arranged so that x-rays emanatingfrom the lower plate, when at least a portion of the electron beam ispassing through a hollow part of the hollow pattern, will not passdirectly from the lower plate through any one of the plurality of holesto the x-ray sensor.